if that happens, knox might have to return to italy. if she refuses, the italian authorities could appeal to the u.s. government for her extradition. if the acquittal is upheld, it's case over. rudy guidea, a native of the ivory coast, is serving a 16-year prison term for kircher's murder. this is the supreme court building where knox's case will be heard. her lawyers will be present as well as the prosecutor for the supreme court. there will be no new evidence, no witnesses, simply a review of the reasoning behind the ruling that set knox free. ben wedeman, cnn, rome. >> all right, ben, thank you very much. at half past the hour, almost. time to check the headlines on cnn. dead of winter? no. almost april. a fierce spring storm, snow storm, springtime snow storm hammered st. louis today. also kansas city, indianapolis and it's coming down hard right now in central ohio as well. the storm brought airports and highways to a standstill in half a dozen states today. >>> the supreme court is set to consider historic cases on same-sex marria